Abstract Type-II superlattice (T2SL) is promising material considered as an attractive alternative to the traditional HgCdTe for IR photodetector applications. Significant progress, such as much improved minority carrier lifetime over 400 ns in the Ga-free InAs/InAsSb T2SL materials, has been demonstrated by ASU team lately. Such a long carrier lifetime has been further confirmed by our LWIR nBn photodetectors demonstrated very recently. It is therefore very desirable to further study the material system, devices as well as related physics. The goals of our current research effort funded by an ARO MURI and an AFOSR/ARO joint program are to study both T2SL materials and photodetectors. At ASU, we currently have facilities for the MBE growth, processing and some optical characterization of T2SLs and devices. In order to better study low density defects present in T2SLs and their direct impact on photodetectors, it is highly necessary to develop a comprehensive and integrated electrical and optical characterization system. The proposed equipment will be integrated with existing setup to enable the measurements such as timeresolved photocurrent measurements, photodetector temporal response, low frequency noise, and their temperature dependences. This program will upgrade our capabilities with a pulsed laser, a low frequency spectrum analyzer, and an upgrade of the FTIR optical spectroscopy system with a step-scan capability and a high throughput PL system for these measurements. In addition to the two program mentioned, the system will support other ongoing research programs at ASU and our collaborating universities and research institutions funded by AFOSR, ARO, NSF and DARPA. It will also be used extensively to train and support dozens of PhD students and postdocs over the next 15 years and to strengthen the established close collaboration with AFRL and ARL, as well as other university in the US.
|Effective start/end date||8/1/14 → 7/31/15|
- DOD-ARMY-ARL: Army Research Office (ARO): $134,584.00